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复杂现象视野下分形理论在建筑学科形态解析中的应用 被引量:8
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作者 浦欣成 张远 《新建筑》 2019年第5期86-91,共6页
文章以国内外建筑学科的分形研究为资料来源,基于面(域)、线(集)、点(阵)的分类视角,回顾并梳理了复杂现象视野下分形理论在建筑学科形态解析中的应用现状,归纳总结出常用的分形维数、分维测度方法、适用范围以及对应表征的建筑意义,综... 文章以国内外建筑学科的分形研究为资料来源,基于面(域)、线(集)、点(阵)的分类视角,回顾并梳理了复杂现象视野下分形理论在建筑学科形态解析中的应用现状,归纳总结出常用的分形维数、分维测度方法、适用范围以及对应表征的建筑意义,综合阐述了分形解析思路的展开、分维测度方法的选择与无标度区间的判别等研究要点,以期为运用分形工具量化解析建筑学科内广泛存在的复杂形态现象提供一定的启发与借鉴。 展开更多
关键词 分形理论 分形维数 分维测度 形态解析 应用
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On the Continuity of Julia Sets and Hausdorff Dimension of N CP and Parabolic Maps 被引量:1
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作者 ZHUANG Wei 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第4期592-596,共5页
Denote by HD(J(f)) the Hausdorff dimension of the Julia set J(f) of a rational function f. Our first result asserts that if f is an NCP map, and fn → f horocyclically,preserving sub-critical relations, then fn ... Denote by HD(J(f)) the Hausdorff dimension of the Julia set J(f) of a rational function f. Our first result asserts that if f is an NCP map, and fn → f horocyclically,preserving sub-critical relations, then fn is an NCP map for all n ≥≥ 0 and J(fn) →J(f) in the Hausdorff topology. We also prove that if f is a parabolic map and fn is an NCP map for all n ≥≥ 0 such that fn→4 f horocyclically, then J(fn) → J(f) in the Hausdorff topology, and HD(J(fn)) →4 HD(J(f)). 展开更多
关键词 Julia set Hausdorff dimension Markov partition conformal measure
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Development of 2D Temperature and Concentration Measurement Method Using Tunable Diode Laser Absorption Spectroscopy 被引量:7
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作者 Yoshihiro Deguchi Daisuke Yasui Akira Adachi 《Journal of Mechanics Engineering and Automation》 2012年第9期543-549,共7页
Exhaust gas temperature is an important factor in NOx, THC and PM emissions of engines. Especially 2D temperature and concentration distribution plays an important role for the engine efficiency. A thermocouple is int... Exhaust gas temperature is an important factor in NOx, THC and PM emissions of engines. Especially 2D temperature and concentration distribution plays an important role for the engine efficiency. A thermocouple is intrinsically a point temperature measurement method and noncontact 2D temperature distribution cannot be attained by thermocouples. Recently, as a measurement technique with high sensitivity and high response, laser diagnostics has been developed and applied to the actual engine combustions. With these engineering developments, transient phenomena such as start-ups and load changes in engines have been gradually elucidated in various conditions. In this study, the theoretical and experimental research has been conducted in order to develop the noncontact and fast response 2D temperature and concentration distribution measurement method. The method is based on a Computed Tomography (CT) method using absorption spectra of water vapor at 1388 nm. It has been demonstrated that the method has been successfully applied to engine exhausts to measure 2D temperature distributions. 展开更多
关键词 2D temperature measurement tunable diode laser absorption spectroscopy CT (computed tomography) engine exhausts.
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Detection of Total Phenols, Essential and Toxic Elements in Latvian Whole Grain Bread
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作者 Natalia Bobere Anton Podjava Ida Jakobsone 《Journal of Chemistry and Chemical Engineering》 2012年第1期1-6,共6页
A survey was carried out with the aim of assessing the level of the total phenolic compounds (TPC), essential (Na, K, Ca, Mg, Cu, Zn) and toxic (Cd and Pb) elements in 10 Latvian whole grain rye and/or wheat flo... A survey was carried out with the aim of assessing the level of the total phenolic compounds (TPC), essential (Na, K, Ca, Mg, Cu, Zn) and toxic (Cd and Pb) elements in 10 Latvian whole grain rye and/or wheat flour bread samples, obtained from the local market. The quantities of the TPC were determined by spectrophotometry. Mineral content was determined by flame photometry, flame atom absorption spectrometry (FAAS) and electrothermal atomic absorption spectrometry (ETAA) after wet digestion in concentrated HNO3. The values were comparable to the literature data. The average content in all the samples was (on a basis of weight of the product) 547 ± 28 mg/100 g for Na; 280 ±20 mg/100 g for K; 32 ± 2 mg/100 g for Ca; 88 ±5 mg/100 g for Mg; 0.49 ± 0.09 mg/100 g for Cu; 1.6 ±0.2 mg/100 g for Zn. Both Pb and Cd were determined below the limit of detection (LOD 5 0.10 mg/100 g). The LOD values were determined for each element. The TPC content in defatted samples was slightly lower than the non-defatted ones, showing the dependence on the sample preparation. The calculated average levels of the elements were compared with the maximum levels recommended or regulated by the national legislation. 展开更多
关键词 Essential and toxic elements whole grain bread flame photometry FAAS ETAA total phenols spectrophotometry.
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Iris Feature Extraction and Recognition Based on Fractal Dimension of Grayscale Extremums
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作者 刘凯 周卫东 +1 位作者 王长宇 王玉 《Journal of Measurement Science and Instrumentation》 CAS 2011年第3期235-239,共5页
This paper presented an individual recognition algorithm for human iris using fractal dimension of grayscale extremums for feature extraction.Firstly,iris region was localized from an eye image with modified circle de... This paper presented an individual recognition algorithm for human iris using fractal dimension of grayscale extremums for feature extraction.Firstly,iris region was localized from an eye image with modified circle detector stemmed from Daugman’s integro-differential operator.Then,segmentation was used to extract the iris and to exclude occlusion from eyelids and eyelashes.The extracted iris was normalized and mapped to polar coordinates for matching.In feature encoding,a new approach based on fractal dimension of grayscale extremums was designed to extract textural features of iris.Finally,a normalized correlation classifier was employed to determine the agreement of two iris feature templates,and the feature template was rotated left and right to avoid the interference from rotation of eyes and tilting of head.The experimental results show that fractal dimension of grayscale extremums can extract textural features from iris image effectively,and the proposed recognition algorithm is accurate and efficient.The proposed algorithm was tested on CASIA-IrisV3-Interval iris database and the performance was evaluated based on the analysis of both False Accept Rate(FAR)and False Reject Rate(FRR)curves.Experimental results show that the proposed iris recognition algorithm is effective and efficient. 展开更多
关键词 iris recognition fractal dimension normalized correlation
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The Dense Fractal Sets with the Hausdorff Dimension
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作者 陆式盘 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2003年第3期410-412,共3页
In this paper, for any given s (0 ≤s≤1), we construct a Cantor-type set E, such that dimH Es- s and Es is dense in [0,1].
关键词 Cantor-type set Hausdorff dimension Hausdorff measure.
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Latitudinal and climatic distributions of 3D craniofacial features among Holocene populations 被引量:1
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作者 PAN Lei WEI Dong WU XiuJie1? 《Science China Earth Sciences》 SCIE EI CAS 2014年第7期1692-1700,共9页
The geographical and climatic patterning in craniofacial morphology among recent hominids has been regarded as relatively reliable evidence of environmental adaptation and natural selection,which is largely attributed... The geographical and climatic patterning in craniofacial morphology among recent hominids has been regarded as relatively reliable evidence of environmental adaptation and natural selection,which is largely attributed to thermoregulation.However,the relative influence of genetic and environmental factors on craniofacial features is unclear.Our study employed 3D laser scanning techniques to evaluate the association between geographical(latitude),climatic(annual temperature)factors,and 3D craniofacial measurements in 18 recent populations through bivariate correlation analysis.Significant correlations were found among braincase surface area,zygomatic bone surface area,cranial-facial index(facial surface area relative to braincase surface area)and local temperature,and a clear latitudinal gradient was also found in variation of braincase surface area.No significant correlations were found between zygomatic bone surface area,cranial-facial index and latitude.Our analysis supports the idea that the braincase functions as a radiator and is closely related to direct sunlight.We also suggest that absolute/relative craniofacial surface area varies consistently with predictions derived from Bergmann’s Rule.The mosaic craniofacial traits of American Indians may reflect retention of cold-derived,ancestral features,as well as a response to a slightly warmer climate.Because different craniofacial regions preserve environmental/genetic signatures differentially,caution is suggested when craniofacial anatomy is used for phylogenetic reconstruction and functional-morphological analysis. 展开更多
关键词 Holocene population craniofacial morphology surface area LATITUDE temperature
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The HAUSDORFF DIMENSION AND MEASURE OF THE GENERALIZED MORAN FRACTALS AND FOURIER SERIES
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作者 REN FUThO LIANG JINRONG 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 1995年第2期153-162,共10页
This paper studies the Hausdorff dimensions, the Hausdorff measures of generalized Moranfrontals and the convergence of the Fourier series of functions defined on some generalizedMoran fractals. A general formula is g... This paper studies the Hausdorff dimensions, the Hausdorff measures of generalized Moranfrontals and the convergence of the Fourier series of functions defined on some generalizedMoran fractals. A general formula is given for the calculatinn of the Hausdorff dimensions ofgeneralized Moran fractals and it is proved that their Hausdorff measures are finite positivenumbers under some conditions. In addition, the authors define an orthonormal system offunctions defilled on generalized Moran s-sets (gMs) and discuss the convergence of the Fourierseries, with respect to of each function f(x) E L1(gMs, Hs). 展开更多
关键词 Haudorff dimension Hausdorff measure s-set Differentiation base Fourier series.
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THE CAPACITY DENSITY AND THE HAUSDORFF DIMENSION OF FRACTAL SETS
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作者 Xu You (Institute of Mathematics, Fudan University, Shanghai 200433, Shanghai, China). 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 1995年第1期43-50,共8页
This paper defines the upper capacity densities of the subsets of R ̄n, gets uniform lower bound of the upper capacity densities for -almost all points of the Hausdorff s-sets or the analytic sets with Hausdorff dimen... This paper defines the upper capacity densities of the subsets of R ̄n, gets uniform lower bound of the upper capacity densities for -almost all points of the Hausdorff s-sets or the analytic sets with Hausdorff dimension s in R ̄n which improves the results of Wen Zhiying and Zhang Yiping's paper in [1]. 展开更多
关键词 Capacity density Hausdorff dimension Fractal set.
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Functional ergodic limits for occupation time processes of site-dependent branching Brownian motions in R
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作者 LI YuQiang 《Science China Mathematics》 SCIE 2014年第10期2053-2072,共20页
We consider a kind of site-dependent branching Brownian motions whose branching laws depend on the site-branching factor σ(·). We focus on the functional ergodic limits for the occupation time processes of the... We consider a kind of site-dependent branching Brownian motions whose branching laws depend on the site-branching factor σ(·). We focus on the functional ergodic limits for the occupation time processes of the models in IR. It is proved that the limiting process has the form of λζ(·), where A is the Lebesgue measure on R and ζ(·) is a real-valued process which is non-degenerate if and only if cr is integrable. When ζ(·) is non-degenerate, it is strictly positive for t 〉 0. Moreover, ζ converges to 0 in finite-dimensional distributions if the integral of a tends to infinity. 展开更多
关键词 functional ergodic theorem site-dependent branching Brownian motion Levy-Khintchine representation
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